| 摘要 |
PURPOSE:To enable easy and accurate measurement of a signal voltage from a signal source having high impedance by switching the impedance of an inputted voltage to be measured at a speed higher enough than that of a signal frequency and by operating an output signal. CONSTITUTION:The source 41 having the signal voltage Vi and an internal signal impedance Zi is connected, being switched by a switch 42, to impedance elements 43 and 44 having impedance Z1 and impedance Z2 respectively. At this time, voltages V1 and V2 obtained from the fall of volt age at the impedance elements 43 and 44 are measured, and by using the ratio in impedance n=Z2/Z1, the voltage Vi of the signal source is found by a formula: Vi=(n-1)V1V2/(nV1- V2). By this method, correct measurement can be performed with a comparatively simple circuit and also measurement which is stable in relation to a thermal change can be conducted. |
